In the decade before man stepped on the moon, before flower children bloomed and Woodstock rocked a dairy farm, dredges began scooping muck from a Boca Ciega Bay inlet to create a marina at the city's southern tip.

More than a half-century later, the owners of Maximo Marina, a sprawling expanse with more than 300 wet slips, are planning an update.

"Everything is old. There are 50-year-old pilings," said project manager Walter Margerison.

"It's time. It's lived its life."

The five-year, six-phase project, with a projected cost of at least $25 million, will begin as soon as government permits have been approved, Margerison said. The plan is to modernize the marina, which draws boaters from Tampa Bay and beyond. That includes the Fort Lauderdale area, considered the yachting capital of the world, as well as northern states and Canada. The Maximo facility, at 4801 37th St. S, also is a winter home for liveaboards.

The multiyear project will not inconvenience the marina's customers, Margerison said.

"We are going to be moving vessels around," he said. "We will have space to accommodate all of our current customers."

Work will be focused on the over-water areas and include updates to electricity, plumbing, water and fire services, and new fixed and floating docks and roofs that meet current hurricane codes. Illinois-based Lincolnshire Maximo, owner since 2009, also is making plans to accommodate larger vessels.

"We are going to cut back on the number of slips so we can make them wider and longer," Margerison said. The marina currently has 326 wet slips, a number that will be reduced to 258 to create the larger spaces.

The Maximo Marina renovations will be a boost to surrounding neighborhoods and a 34th Street South Corridor Plan aiming for increased retail and redevelopment in a 1.5-mile stretch between 30th and 54th avenue S.

Neighborhood leaders and business owners were told in a recent presentation that the facility is the state's largest covered wet slip marina. Additionally, Joshua Maxwell of Turrell, Hall & Associates in Naples, a marine and environmental consulting firm, gave an overview of the marina's amenities, which include dry storage and a service center. He also spoke of improvements to come.

"We took the existing facility, analyzed it and found any deficiencies and modified the existing layout to meet today's current fleet," Maxwell said during an interview. "We also looked at the power demands and made sure that the new utilities would be adequate."

Much has changed since the facility — once known as Maximo Moorings Marina — rose at the end of the 3,700-foot-long, 200-foot-wide canal dredged in the years before strict environmental regulations.

Jon Wilson, a former Tampa Bay Times reporter, chronicled the birth of the marina and surrounding community — developed by New Yorkers Morty and A.B. Wolosoff — in his book, Golden Era in St. Petersburg: Postwar Prosperity in the Sunshine City.

"The Wolosoff brothers decided to make a marina the centerpiece of their development after learning that every docking venue in St. Petersburg was full and had a waiting list," Wilson wrote.

"Finished by the late 1950s, Maximo Moorings' promoters billed the docking facility as the world's largest covered marina. Dredge crews pulled up muck from the bottom of a Boca Ciega inlet, using it to fill low spots in the subdivision."

A boat ride along the Maximo canal reveals an active boating community, with vessels occupying nearly every residential dock along the waterway, which is owned and maintained by the marina.

A recent tour of the facility, which occupies the eastern and western sides of 37th Street S, showcased sprawling docks and a busy boat yard for repairs and service. This particular day, a worker could be seen scraping barnacles from the bottom of one of several boats that had been hoisted from the water. Across the street, dozens of boats were in dry storage. Next door were offices leased for boat sales.

On the waterside, space once occupied by Leverock's Seafood House, closed in 1994, is mostly empty.

"We are looking and talking to other people and maybe there's the possibility of getting a restaurant there at some point," Margerison said.

Further down on the main dock, though, the Maximo Seafood Shack caters to cravings from alligator tail to grouper. Owner Margaret Covello fillets, cooks and sells fresh catch in to-go containers for customers to savor with beer or wine while taking in her shop's waterfront vistas. Covello hopes to keep the Old Florida look after the marina is renovated.

Margerison agreed. "We'd like to keep that flavor."

Work on the first phase of the multimillion-dollar project will begin in the marina's southwestern end, where a covered dock will be demolished. New fixed docks without roofs will take its place and a new seawall built.

It will be like a new marina when the project is complete, Margerison said.

"It's going to bring a basically state-of-the-art marina facility to this area of St. Petersburg, with basically all the amenities Maximo Marina has always provided, but on a better scale," Maxwell said. "It would be back to the hurricane hole it was back in the '50s and '60s."

Times researcher Caryn Baird contributed to this report. Waveney Ann Moore can be reached at wmoore@tampabay.com or (727) 892-2283.